VCCA Home Forums TECHNICAL - GENERAL Body - Sheet Metal, Paint & Wood Firewall grommet '33-36 All & '37-'46 Trucks

If anyone out there has a 1933-46 Chevy with an electrolock cable passing through a 1 3/8” hole in the firewall at an angle this home made rubber grommet just finished today may be of interest. It is made from a 1 3/8” rubber panel plug. A hole was made at an angle to the firewall to match the angle of the cable. A fixture was made to hold the rubber plug in slight compression to prevent any tearing of the rubber during making the angle hole that was done with a 3/8” hole saw and a 3/8” end mill, both running at a high speed.

Photos of the hole making process and installed finished product available to interested do-it-yourselfers on the Stovebolt forum:

https://www.stovebolt.com/ubbthread...t-3-36-all-37-46-trucks.html#Post1366584

The minimum purchase quantity of the panel plug I started with is 2 so I will probably make another one of these grommets while I have the setup. Maybe some other 1930s or 1940s Chevy or GMC owner will want to try it.

Ray W

There is a grommet listed in the Steele Rubber catalog, PN:50-0327-20, listed as:Grommet, speedometer cable through firewall (lower). Replaces factory #1321172. It has the angled 3/8" hole drilled through it like you describe. There is also another grommet listed as:Grommet, firewall, parking brake cable, has three eighths (3/8) inch angular hole through one and one fourth (1-1/4) inch diameter grommet. This also has the hole drilled at an angle. Would either of these be the same as what you are making. I have a 35 Chevy and need both, or 2. One for my speedometer cable coming up through the toeboard / firewall, and one for the electrolock cable going through the firewall. Any info would be helpful. Thanks. If the ones in the catalog aren't the ones that I need, I may be interested in 2 of yours. Thanks again, Pete V

Hi Pete,

I bought 2 "Solid Push-in Plugs" for a 1 3/8 inch panel hole because after a long search I concluded that there is no grommet available for a 1 3/8" hole in a 1/16" thick panel (the firewall) with a 3/8" center hole.

Being a do-it-yourselfer who actually enjoys projects like this I decided to make my own grommet. One plug was all I needed but the minimum purchase that I could find was 2. The one I didn't use is still just as I got it.

The photo of the finished grommet on the Stovebolt forum is out of focus, apparently because the camera decided to focus on the 4-hole grommet in the center of the firewall instead. If you send me a message with you email address I'll send you a better photo of the finished grommet installed.

I've had the same '36 Chevy PU since 1965 and I've discovered some surprising parts interchanges, some even with other brands like Ford, Toyota, Porsche and Jeep, and some of what I call "Stealth modifications" (invisible but effective) that make it safer and more pleasant to drive.

Steele Rubber products are outrageously overpriced, aimed at the Duesenburg and Bugatti dilettantes, not us plain folks with Chevies. Have you searched online for the other grommets you need?

Ray W